Dunkin Refresher (medium) carries more total caffeine per serving (99mg per 24 oz medium vs 80mg per 8.4 oz can), but ounce for ounce Red Bull is actually the stronger drink at about 10mg per fluid ounce against 4. Which one "has more caffeine" depends on whether you measure the container or the concentration.
These are different categories of drink, which changes how the caffeine arrives. Energy drinks and sodas list an exact number because caffeine is a measured additive; brewed drinks vary with the beans and the brew, so their figures are compiled averages. The numbers here are the standard published values for each.
Dunkin Refresher (medium) vs Red Bull: the numbers
| Dunkin Refresher (medium) | Red Bull | |
|---|---|---|
| Caffeine per serving | 99mg per 24 oz medium | 80mg per 8.4 oz can |
| Caffeine per fl oz | 4.1mg | 9.5mg |
| Servings to reach 400mg (FDA context) | 4.0 | 5.0 |
Sources: Dunkin Refresher (medium)'s figure is verified in our Dunkin Refresher (medium) caffeine guide against Tasting Table / Dunkin figures (source); Red Bull's figure is verified in our Red Bull guide against Red Bull label / Caffeine Informer (source).
Which one should you pick?
Pick Red Bull when you want the lighter dose or a slower ramp, and Dunkin Refresher (medium) when you actually need the bigger hit and know your tolerance. If you are stacking either with other caffeinated drinks through the day, run the math against the 400mg reference rather than guessing.
For context, the FDA cites 400mg of caffeine a day as an amount generally not associated with negative effects in healthy adults. Tolerance and health vary, so treat these numbers as information, not advice.
Related reading
- Dunkin Refresher (medium): the full caffeine guide
- Red Bull: the full caffeine guide
- The verified caffeine database
FAQ
Does Dunkin Refresher (medium) or Red Bull have more caffeine? Dunkin Refresher (medium): 99mg per 24 oz medium versus 80mg per 8.4 oz can for Red Bull.
Which is stronger per ounce? Red Bull, at about 9.5mg per fluid ounce versus 4.1mg for Dunkin Refresher (medium).
Barista Life runs on coffee people. Browse the Barista Life shop to support the site.